Auxiliary trigger mechanism for firearms



Aug. 19, 1952 c. -E. SIMPSON 2,607,148

AUXILIARY TRIGGER MECHANISM FOR FIREARMS Filed June so, 1949 PatentedAug. 19, 1952 AUXILIARY TRIGGER MECHANISM FOR FIREARMS Clarence E.Simpson, Springfield, Mass., assignor to the United States of America asrepresented by the Secretary of War Application June 30, 1949, SerialNo. 102,186

(Granted under the act of March 3, 1883, as

3 Claims.

amended April 30, 1928; 370 0. G. 757) The invention described hereinmay be manufactured and used by or for the Government for governmentalpurposes Without the payment of any royalty thereon.

This invention relates to an auxiliary trigger mechanism for use in theoperation of firearms under extreme cold weather conditions.

It has been determined that heavy fingerless mittens offer the utmostprotection to the hands against extreme arctic Weather. However, the useof such fingerless mittens introduces considerable difiiculty in theoperation of firearms and especially in the manipulation of the trigger.7

Accordingly, it is an object of this invention to provide a firearm withan auxiliary trigger mechanism which can be readily actuated even whenthe operator is encumbered with heavy fingerless mittens.

It is a specific object of this invention to provide a firearm with anauxiliary trigger mechanism which can be readily inactivated at the willof the operator to permit normal manipulation of the conventionaltrigger.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

Fig. 1 is a side elevational view shown partly in cross-section of theauxiliary trigger mechanism of this invention.

Fig. 2 is a cross-sectional view taken along the line 22 of Fig. 1 andshowing the blocking member in position to prevent actuation of theauxiliary trigger.

Fig. 3 is a bottom view of the pistol grip.

Fig. 4 is a cross-sectional view similar to Fig. 2 but showing theblocking member in position to permit actuation of the auxiliarytrigger.

Fig. 5 is a perspective View of the auxiliary trigger.

Although the auxiliary trigger of this invention is here shown adaptedfor use with a firearm having a so-called "pistol grip stock, it shouldbe understood that a trigger of this type is equally applicable to thoseweapons having a straight conventional stock.

There is shown in Fig. 1 a portion of a firearm having a dependingpistol grip 5 and a trigger guard 6 extending forwardly therefrom. Aconventional trigger l is pivotally mounted Within trigger guard 6 as bya pin 8. A sear spring 9 is arranged to bias a pivotal sear [0 intoreleasable engagement with trigger I. A safety member H is rotatablymounted in the firearm above trigger guard 6 for movement between an onand off position and is slotted as shown at [2 to permit actuation oftrigger 1 during the off position. The forward pivotal movement oftrigger I is limited by a suitable stop surface I3 located withintrigger guard 6 and the rearward pivotal movement is limited by safetymember I I. Trigger 1 is provided with a finger piece 31 arranged toextend into a vertical opening l4 provided through the bottom of triggerguard 6 The front face of pistol grip 5 is contoured to provide aforwardly projecting portion It at the bottom thereof. A substantiallysemi-elliptical recess [5 is provided in the front face of pistol grip 5and terminates sufficiently above the bottom of grip 5 to extendslightly into forwardly extending portion I6. A pair of spaced apartrelatively narrow slots I! extend vertically through portion [6 asindicated in Fig. 3.

Recess I5 and slots I! are arranged to receive an auxiliary trigger l8which is pivotally secured to pistol grip portion [6 as by a pin [9 orthe like. Auxiliary trigger [8, as best shown in Fig. 5, comprises achannel-shaped body portion 20, the outer surface thereof being suitablycontoured to conform to the grasp of either a bare or mittened hand, anda forwardly extending integral head portion 2! arranged to lie beneathtrigger guard 6 when trigger I8 is assembled to pistol grip 5. Anupstanding lug 22 is provided on head portion 2| and extendssufficiently into vertical opening M of trigger guard 6 to engage fingerpiece 31 of trigger I when auxiliary trigger I8 is pivoted about pin [9.A flat rectangular portion 23 disposed at right angles to each rearmarginal edge 24 of auxiliary trigger body portion 20 is provided with arearwardly projecting ear 25 for a purpose to be shown.

A hole 26 extends transversely through pistol grip 5 and is located soas to partially intersect recess l5 substantially midway with respect tothe vertical axis of grip 5. A blocking member 21 is arranged toslidably engage in hole 26 and comprises in adjacent relationship acylindrical section 28 at one end, a step portion 29, a first reduceddiameter section 30, a forwardly tapering section 3| having a minimumdiameter slightly less than that of step portion 29, a second reduceddiameter section 32, and a cylindrical section 33 at the other end ofblocking member 21. A suitable indentation 34 is formed in end sections28 and 33 for receiving a drift or the nose of a bullet by means ofwhich blocking member 21 can be moved transversely in either aco'niee 28is forced apart slightly so as to increase the Consequently, endsection'28 is frictionally engaged in hole 26 and thereby, preventsaccidental movement of blocking mem-x diameter thereof.

[6. Movement of auxiliary trigger I8 is limited by the allowablemovement of trigger l which depends upon the depth of slot I2 in safetymember H. When auxiliary trigger H3 is depressed, ears extend beyond therespective peripheries of'cylindrioalend sections 28 and 33 and therebyprevent blocking member 21 from protruding beyond either outside surfaceof pistol grip 5. When released, auxiliary trigger I8 is pivoted back toits pre-firing positionby conventional trigger I through the bias ofsear spring 9.

When blocking member 27 is moved to the position shown in-Fig. 2, one ofthe cars 25 rides onto tapered section 3| while the other contacts theperiphery of step portion 29. Thus movement of auxiliar trigger i8 isblocked while conventional trigger l is free to be actuated in a normalmanner when safety H is in the off position. When safety H is in the-onposition, movement of trigger 7 is prevented and consequently auxiliarytrigger [-3 can-not be actuated even though blocking member 21 is in theposition shown in Fig. 4. ment of blocking member 21 and consequentlythe extent to which ear 25 rides up onto tapered section '3! is governedby the contact of lug 22 with the inner front surface of verticalopening M in trigger guard 6. It can thus bereadily seen that anyexisting backlash of auxiliary trigger [8 in its safe position isadequately taken up and furthermore that the vibration and shock offiring will not result in any accidental movement of blocking member 21and consequently auxiliary trigger l8. 1

Another advantageous structural feature of this invention resides in theprovision of a chamfered marginal edge 36 for semi-elliptical recess 15.As a result, the flesh of the handor the fabric of a mitten can not beaccidentally pinched between auxiliary trigger l8 and'pistol rip 5.

Thus there is here provided a simplebut effective auxiliary triggermeans which can be readily manipulated by the operator of the firearmeven with the heavy fingerless mittens commonly worn in extreme arcticweather. At the same time, thefirearm can be quickly converted to theuse ofthe conventional trigger at the will of the operator by simplypushing a blocking member in the required direction. Furthermore the useof "auxiliary trigger 18 introduces the squeeze method of triggerrelease which is believed by many to be superior to the conventionalpull required to release a trigger.

I claim:

1. In a firearm having a pistol grip,-the' combination of a pivotalprimary trigger and auxiliary trigger means comprising an auxiliarytrigger pivotally mounted in the pistol grip and The transverse move-- 4protruding forwardly therefrom in order to be readily grasped by amittened hand, lug means on the free end of said auxiliary trigger foractuating said primary trigger when said auxiliary trigger is squeezed,and means for blocking movement of said auxiliary trigger wherebydischarge of the firearm can be effected only by directly pulling saidprimary trigger.

2. In a firearm having a pistol grip terminating in a forwardlyextending trigger guard provided with 'a slot extending verticallythrough the bottom thereof, the combination of a primary triggerpivotally mounted in the trigger guard so that the free end extends intothe slot thereof and auxiliary trigger means comprising an auxiliarytrigger pivotally mounted at its lowerend in the pistol grip andprojecting forwardly therefromto permit ready grasping by a mittenedhand, an upstanding lug on the free end of said auxiliary triggerarranged to extend into the trigger guard slot forwardly of the free endof said primary trigger whereby actuation of said auxiliary triggersimultaneously actuates said primary trigger, and means for blocking theactuating movement of said auxiliary trigger whereby discharge of thefirearm can be effected only by directly pulling said primary trigger.

3. In a firearm having a pistol grip terminating in a forwardlyextending trigger guard, the

combination of a primary trigger pivotally mounted in the trigger guardand auxiliary trigger means comprising an auxiliary trigger pivotallypinned at its lower end adjacent the bottom of the pistol grip, theforward edge of the grip being cut away to form a semi-elliptical recessfor receiving said auxiliary trigger so that the forward portion thereofprojects from said recess in position to be readily grasped by amittened hand, lug means integrally formed on the free end of saidauxiliary trigger and extending upwardly therefrom to contact the frontedge of the free end of said primary trigger, and a blocking memberslidably mounted in the pistol grip in the path of movement of saidauxiliary trigger whereby transverse movement of said member in onedirection blocks the actuating movement of said auxiliary trigger sothat discharge of the firearm can be effected only by a direct pull onsaid primary trigger and whereby transverse movement of said blockingmember in the opposite direction frees said auxiliary trigger so thatactuation thereof will also simultaneously actuate said primary triggerto discharge the firearm.

CLARENCE E. SIBAPSON.

REFERENCES CITED Thefollowing references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,569,856 E riksen Jan. 19, 19261,837,093 Andrews Dec. 15, 1931 2,000,858 Maxwell May '7, 1935 2,225,583Blizard Dec. 1'7, 1940 2,433,309 Van Karner Dec. 23, 1947 FOREIGNPATENTS Number Country I Date 15,065 Great Britain of 1897 326,260France Feb. 16, 1903 554,287 Germany July '7, 1932

